Lua

Fetch a Text IMAP Attachment as a String

Demonstrates the Chilkat Imap.FetchAttachmentString method, which returns one text attachment decoded to a string. The first argument is the Email, the second is the zero-based attachment index, and the third is the charset used to decode the bytes. This example returns the first attachment as a UTF-8 string.

Background: This is the convenient form when you simply want a small text attachment's content inline as a string. Only use it for attachments known to be text; decoding binary content through a charset can alter or corrupt the bytes. For binary data use FetchAttachmentBd, and for large text a StringBuilder (via FetchAttachmentSb) avoids an extra copy.

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Lua

local chilkat = require("chilkat")

-- Demonstrates the Imap.FetchAttachmentString method, which downloads one text attachment and
-- returns it decoded to a string.  The 1st argument is the Email, the 2nd is the zero-based
-- attachment index, and the 3rd is the charset used to decode the bytes.
--
-- The message is fetched headers-only, then the attachment is downloaded on demand.

local imap = chilkat.Imap.new()

imap.ssl = true
imap.port = 993

local success = imap:connect("imap.example.com")
if not success then
    print(imap.last_error_text)
    return
end

success = imap:login("user@example.com", "myPassword")
if not success then
    print(imap.last_error_text)
    return
end

success = imap:select_mailbox("Inbox")
if not success then
    print(imap.last_error_text)
    return
end

-- Fetch only the message headers.  Attachment bodies are NOT downloaded, but the ckx-imap-*
-- metadata describing the attachments is present, so the attachment info methods still work.
local headersOnly = true
local useUid = false
local seqNum = 1
local email = chilkat.Email.new()
success = imap:fetch_email(headersOnly, seqNum, useUid, email)
if not success then
    print(imap.last_error_text)
    return
end

local numAttach = imap:get_mail_num_attach(email)
if numAttach > 0 then
    -- FetchAttachmentString returns a string, so assign it to a string variable.
    local attachText = imap:fetch_attachment_string(email, 0, "utf-8")
    if not imap.last_method_success then
        print(imap.last_error_text)
        return
    end

    print(attachText)
end

success = imap:disconnect()
if not success then
    print(imap.last_error_text)
    return
end